Telescopic radar antenna



Feb. 10, 1970 w; R. LASTINGIER ETAL 9 TELESCOPIC RADAR ANTENNA Filed May 8, 1968 z r I 2 f/vvewroes. 71 74/044 B lfisr/Nsse Nswz-zz. J O en/v52 IQTTOENEIJ.

United States Patent US. Cl. 343709 Claims ABSTRACT OF THE DISCLOSURE A telescopic antenna for submarines, boats, or the like, in which a mast extends upwardly through the top or deck of the boat or submarine and is extensible to raise a directive radar antenna to a relatively high level :to avoid envirnomental ship structure, but is telescopically retractable, if necessary, during heavy weather, submergence, or otherwise, the antenna being of the paraboloidal type and the mast containing directive guides and focusing lenses for directing the waves to and from a radar transceiver. Such an antenna in which the structure is sealed to enable fluid pressure extension of the mast.

Various telescopic radio antennae and anntena masts have been heretofore provided for use on boats, as well as other vehicles, but the typical radar antenna masts are of fixed height, generally installed so as to be at a desired elevation relative to the environmental structure of the boat for optimum efficiency in the operation of the radar system in scanning the field as the antenna is rotated.

As a consequence of such mounting of the typical radar antenna on the boats, such as pleasure and sportsfishing boats, the antenna mast and the antenna proper are at all times in fixed locations or elevations, which locations may not be at all times practical or desirable. For example, in fair weather, when the radar system is idle, it may be preferable that the mast and antenna proper be movable to an out-of-the-way or out-of-sight location, either for purposes of afiording unrestricted vision to the pilot while visually searching for signs of fish, or removing an impediment to the effective handling of a fish when being played by a fisher-man, say if the fish should tend to circle the boat, tending to carry a line past an upstanding antenna mast.

On the other hand, in some weather, such as heavy wind and waves, it may be perferable to have the radar antenna at a lower location to protect it from the eifect-s of the wind and water. If the antenna is at a fixed, high elevation, which may be preferable for efiiciency of radar signal transmission and reception, the tall mast would be inherently be subjected to severe force-s, particularly if the boat is being washed by waves in a heavy sea.

Accordingly, the present invention provides an antenna mast construction which is telescopic in nature, so that the antenna may be elevated, say to a height at which optimum radar operation is attainable, but when desired or necessary, the antenna may be lowered to a more sheltered location which may be out of the way and afford safety from the hazards of high wind and waves.

In accomplishing the foregoing, the invention provides a telescopic mast assembly including a base section which may be rigidly mounted, say at the keel 0f the boat, and may extend upwardly through the cabin top or deck of the boat. Above the cabin top or deck, the base section telescopically supports one or more extensive sections, adapted to be elevated in the illustrative embodiment by fluid pressure, which may be raised or lowered as desired, to raise or lower the antenna proper between an uppermost position elevated well above the cabin top or deck,

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and a lowermost position closely adjacent to the cabin top or deck.

More particularly, the invention provides a sealed telescopic antenna mast construction having at the upper end of the uppermost telescopic section a support for an antenna, such as a typical parabolidal reflective antenna, and drive means, or a motor and gear means, for effecting rotation of the support, the mast having therein wave guide means and lens means for directing the signals between the antenna and a transceiver which may be suitably located in the boat.

Among the objects of the invention is provision of an eflicient signal or wave guiding means within a rugged telescopic mast assembly which may easily raised or lowered as may be desired or necessary in the use of the boat, or the like, equipped with the antenna, or in the use of radar equipment employ-ing the antenna.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming par-t of the present specification. it will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a view, partly in elevation and partly in section, showing an antenna and mast in accordance with the invention installed in a boat, or the like, and in retracted condition; and

FIG. 2 is an enlarged fragmentary view, more particularly showing the details of the rotatable antenna support and the telescopic mast in extended condition.

Referring to FIG. 1, there is illustrated an antenna installation wherein a telescopic mast M, with an antenna A revolvably supported at the top of the mast, is applied to a boat, the keel 1 and a cabin top or deck 2 of which are shown by way of illustration of a mode of installatron.

More specifically, the telescopic mast M includes a tubular base section 3 having a base plate or supporting bracket 4 at its lower end. This base plate 4 is adapted to be secured by fastenings 5 at a desired location to the keel 1 of the'boat, or to some other horizontal structural member which affords a rigid mounting for the base plate 4. The base section 3 of the mast M may be of any desired height, but preferably is of such dimension as to extend upwardly through the cabin top or deck 2 of the boat through an opening which is suit-ably scaled as at 6.

While the mast may include any number of upper tel scopic sections, the herein illustrated embodiment includes an upper tubular section 7 which slid-ably telescopes within the base section 3 of the mast. For purposes of assembly, the base section 3 may have a bushing or cap 8 threaded therein as at 9, and having an inwardly extended flange 10, the flange 10 being provided with a suitable sealing ring 11 for sealing engagement with the outer cylindrical wall of the mast section 7.

At its lower end, the mast section 7 is provided with a flange 12 which supports a suitable bearing assembly 13 adapted to shiftably engage with the inner cylindrical Wall of the base section 3 of the mast M. Abutment of the flange 12 of the upwardly extensible mast section 7 with the flange 10 of the bushing 8 determines the maximum extension of the telescopic mast. It will be understood that if additional extensible sections are employed, similar sliding joints and seals may be employed for each additional mast section.

At its upper end, the extensible mast section 7 is provided with revolvable support means S for the antenna A. This revolvable support means comprises a collar 14 revolvably mounted on the mast section 7, as by suitable sealed bearing means, which may comprise bearing elements or balls 15 engaged in opposing annular grooves within the collar 14 and on the mast section 7 and having a seal 17 which engages between the mast section and the collar, the collar 14 being retained on the mast 7 against axial displacement by the balls 15. Suitably provided about and fixed to the collar 14 is a gear 19, whereby the collar may be rotated by a pinion 20 which meshes with the gear 19 and is driven by an electric motor 21. This motor 21 may be suitably supported, as by a bracket 22, which is connected to the mast section 7. A source of power for the motor may be provided in any conventional manner.

An antenna mount 23 is included in the revolvable support structure S, including a cylindrical portion 24 which is disposed in the collar 14 and sealed by a seal ring 25, fasteners 26 or other means being employed to hold the mount 23 on the collar 14. Extending through the mount 23 is an opening having a seal ring a for pressure-tight engagement with a sealed wave guide tube 27 extending downwardly from the antenna A.

It is now apparent that the telescopic mast assembly M is sealed in such a manner that fluid under pressure may be supplied internally thereof, so as to elevate the extensible mast section 7. Thus, the base section 3 of the mast is shown as having communication with an air or other fluid inlet conduit 28, and with an outlet conduit 29. These conduits may be provided with suitable valve means 28a and 29a so that the admission of fluid under pressure to the interior of the mast and exhaust of the telescopic assembly may be selectively controlled to cause extension of the assembly and allow retraction thereof. The mass of the extensible section 7 and the antenna A may be relied upon to cause the section 7 to lower itself upon exhaust of the assembly, but, if desired or necessary, the extensible section may be provided with means for forcibly lowering the same.

Within the mast assembly M are means for directing the RF or radar signals within the mast itself and between the antenna and the signal transceiver. Thus, as seen in FIG. 1, there is a conventional sealed wave guide 30 having its end 31 disposed in and directed axially upwardly in the base mast section 3 toward a lower planoconvex RF lens type refractor 32. In the upper portion of the extensible mast section 7 is an opposing planoconvex RF lens type refractor 33 in axial alignment beneath the wave guide 27, previously referred to, which extends into the mast section 7 from the antenna A.

This latter wave guide extends into a parabolic reflector 34 of the typical marine type antenna A from and into which signals are reflected by a cylindrical parabolic reflector through a window 36. The details of the antenna A, per se, need no further description or illustration herein since such structures are well known and conventional. An example of another specific antenna structure which may be mounted upon the mount 23 in any suitable manner is the directive antenna of United States Letters Patent No. 2,427,005.

In the use of the present invention, say when it is desired to elevate the antenna A, air or other fluid under pressure may be admitted to the antenna structure through the conduit 28, the valve 29a in conduit 29 being closed. The extensible mast section 7 will thus be elevated from the lowered position of FIG. 1 to the elevated position of FIG. 2, or to some intermediate position, as desired. When power is supplied to the motor 21, the antenna A will be caused to revolve.

Signals transmitted by a radar transceiver will pass through wave guide 30 into the mast, and will be focused by RF lenses 32 and 33 into the wave guide 27, and thence by the reflectors 34 and 35 outwardly in a generally hori zontal plane to any object within the range of the signals. Reflected signals from such object will return to the transceiver in the opposite manner.

When it is desired that the antenna be lowered, say in the event of heavy weather, the valves 28a and 29a will be reversed, that is, the valve 28a closed and the exhaust valve 29a opened, exhausting the mast M so that the extensible section 7 may descend by gravity into the base section 3.

We claim:

'1. A telescopic antenna mast comprising: a tubular base mast section, an extensible mast section telescopically supported by said base mast section, sealing means between said rnast sections, a rotatable antenna support at the top of said extensible mast section, sealing means between said rotatable antenna support and said extensible mast section, means for admitting fluid under pressure into said mast and exhausting fluid therefrom for effecting telescoping of said mast, and signal directing means for guiding signals into and along said mast.

2. A telescopic antenna as defined in claim -1, wherein said signal directing means includes a wave guide leading into said base mast section, and focusing lens means above said wave guide.

3. A telescopic antenna as defined in claim 1, wherein said signal directing means includes a wave guide leading into said base mast section, focusing lens means above said wave guide, and a wave guide in said rotatable antenna support for directing signals between said mast and an antenna revolvable with said antenna support.

4. A telescopic antenna as defined in claim 1, including motor means on said extensible mast section and drivingly connected to said rotatable antenna support.

5. A telescopic antenna as defined in claim 1, wherein said rotatable antenna support includes a collar, sealed bearing means rotatably mounting said collar on said extensible mast section, and an antenna mount sealingly engaged with said collar.

6. A telescopic antenna as defined in claim 1, wherein said sealing means between said mast sections includes means for limiting telescopic extension of said mast.

7. A telescopic antenna mast comprising a base section, an extensible and retractable section telescopically engaged with said base section, a wave guide in said base section adapted to be connected with a signal transceiver and to direct waves axially in said mast, rotatable antenna support means at the upper end of said extensible and retractable mast section, means for rotating said support, and a wave guide in said support adapted to direct signals between the first-mentioned wave guide and an antenna on said support.

8. A telescopic antenna mast as defined in claim 7, wherein said base mast section includes a signal focusing lens above said wave guide in said base mast section, and said extensible mast section includes a signal focusing lens below said wave guide in said support.

9. A telescopic antenna as defined in claim 7, wherein said motor means includes a pinion driven by said motor means and a gear connected to said support and meshing with said pinion.

10. A telescopic antenna assembly adapted to be installed in a boat, comprising a base mast section having a base support connectible to the keel of the boat, an extensible mast section telescopically engaged with said base mast section and extensible above the top of the boat, a directive antenna at the top of said extensible mast sec tion, a rotatable support for said antenna revolvably disposed on said extensible mast section, means for revolving said support, a wave guide extending from said antenna into said extensible mast section and directed axially in the latter, a wave guide in said base mast section and directed axially thereof, and signal focusing means in said mast sections between said wave guides.

(References 011 following page) 6 References Cited RODNEY D. BENNETT, JR., Primary Examiner UNITED STATES PATENTS RICHARD E. BERGER, Assistant Examiner 2,861,268 11/1958 Tinsley 343883 X 2,940,078 6/1960 Bodmer et a1 343 -ss3 X 3,158,865 11/1964 McCorkle 343-4383 X 5 343766, 783, 883, 884 

